1. Field of the Invention
The invention relates to an assembly for retaining a boot on a gliding board. In a particular embodiment, the invention relates to an assembly for retaining a boot on an alpine ski.
2. Description of Background and Relevant Information
In order to retain a boot on an alpine ski, one ordinarily uses retaining elements, i.e., bindings, that release the boot when the forces, or stresses, between the boot and the board exceed a predetermined threshold.
In a conventional manner, one uses assemblies that are completely mechanical for detecting such forces and for ensuring the release of the boot. For these types of assemblies, all of the energy required to cause the opening of the jaw is produced by the boot.
These assemblies have until now yielded positive results. Nevertheless, the processing that results from the detection of stresses is relatively limited. Generally, only an instantaneous stress is measured in a given direction, and this stress is used to cause the opening of the retaining jaw. In a conventional manner, one allows the jaw to displace itself against the return force of a spring, and the boot is released when it pushes the jaw beyond a predetermined position. Under these conditions, the boot is displaced with the jaw, which requires providing gliding surfaces between the boot and the retaining elements so as to control, as much as possible, the friction of the sliding of the boot with respect to its various supports or support surfaces. These constructional stresses make the boot uncomfortable for walking.
Studies have been conducted to detect stresses and to process the data electronically instead of mechanically. The detecting means or apparatus that are the most commonly proposed are stress gauges that are positioned in the connection between the boot and the ski. Various solutions for processing the electric signals are known that take into account both the duration and the intensity of the stresses detected. As for the member that causes the release of the boot, it has been proposed to use an electromagnetic or a pyrotechnic-type release device.
The published applications FR 2 351 678 and FR 2 374 922, and their family members, U.S. Pat. No. 4,160,555 and U.S. Pat. No. 4,383,702, respectively, describe a system for detecting and electronically processing stresses. The published application EP 0 346 414 describes an electromagnetic-type release, and the published application FR 2 364 045, and family member U.S. Pat. No. 4,121,854, describe a pyrotechnic-type release.
The drawback with an electromagnetic-type release is that it requires a substantial source of energy in order to provide sufficient energy to the electromagnet that controls the opening of the jaw. Additionally, it is difficult to control the phenomena of discharging the battery over time.
A pyrotechnic-type release is capable of providing a substantial instantaneous energy; however, the number of releases possible before recharging the system is completely limited.
Consequently, there is a need for a system for retaining a boot on a gliding board in which the energy source that controls the opening of the jaw is capable of providing a substantial energy under a light volume and loaded weight, and allows for a relatively substantial number of releases before requiring a recharge.